Im not new to nitro and I can tune a motor really good but im working on my very first 90 size heli,ive never tuned a 3 needle carb .I got a ThunderTight pro 90 and alot of people said its a good motor but not the best for 3D that I should get a OS or YS.I got enough money for Xmass,seen this motor and snagged it up https://rc.runryder.com/helicopter/t561669p1/ .3 questions.1 how much better is the motor I picked up?2 This is my first 3 needle carb so should I learn to tune the TT Pro 90 before running the OS?3 Is there any tips I should do?Thanks..

Hell... I can fix that.Uh oh..Nope.It's ***ked!!! RE-KIT!!!!!

Go with the OMI CSPEC.
I have run the hell out of those motors and they are fantastic.
What type of fuel will you be running, and what is altitude at your flying field? And what pipe will you run?

At sea level here in VA, running CY30% I needed to run at least .016 head shim in that motor (two thick OS shims). If you are up above 1000 feet above seal level you may not need as much. If you run a fuel with a different oil package you may not need as much.

Anyway, on 30%CY, with .016 to .020 shim, that carb (that is an SZ carb with a OMI mod to add the Cline) you need idle about center, midrange around 1/2-5/8 and main needle somewhere around 1-1/2 (I run a touch closer to 1-1/4, but it depends on your flying style.
Best pipe would be a Hatori SB18/1900 or possibly an MP6. Shoot fpor about 15000 to 15250 in idle up.

Jim Senicka Team Manager, GrandRC Flight Team

Thanks for the replys guys and i'll go with the C Spec.Not sure what pipe I have but i'll upload a pic in a min.I have no ideal where im at (sea level) but im in Michigan if that helps .As for fuel i'll be running CY WildCat 30% performance,not the heli-mix.Once I get the motor i'll strip the whole thing down to check bearings ect..like I allways do and i'll check to see how many head shims are on it.It allready sounds like I did good getting this motor,im not sure what flying style im at (see video) but i'll guess and say mild 3D .I take it the TT pro 90 won't hang with my flying?

What are you going to do with the TT-90?

Did you get the check valve that shipped with the OMI Cline regulator mod to the carb?

This motor gets plumbed like the YS 50 -- crankcase pressure tap on the back plate -- short piece of hose with the check valve inserted followed by a Tee fitting. The second end of the Tee goes to the tank vent, the third end of the Tee gets a short hose with a plug.

Main tank outlet goes to input of a Tee/filter. The filtered outlet of the Tee goes to carb fitting, the third fitting of that Tee gets a short hose with a plug for filling.

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That elbow fitting on the Cline regulator has been known to separate from the regulator and many people report they have not found a solvent that will keep the fitting in place. People who use the Cline recommend NOT using the elbow at all, but rather cleaning the nipple very well and using a piece of new fuel tubing plugged directly onto the nipple.

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I run that motor and carb/regulator mod in my Trex 700. This picture pretty much shows the entire fuel plumbing setup, including the Cline regulator.

-----Dave

* Making the World Better -- One Helicopter at a time! *

Team Heliproz

I have alot to learn haha.The motor gets shipped Saturday and I didn't know I would need the check valve,I just sent him a pm asking if it comes with the motor but if not where can I get one at?Im saving this thread to my Favorites so I know how to run the plumming and thanks so much for letting me know .

That elbow fitting on the Cline regulator has been known to separate from the regulator and many people report they have not found a solvent that will keep the fitting in place. People who use the Cline recommend NOT using the elbow at all, but rather cleaning the nipple very well and using a piece of new fuel tubing plugged directly onto the nipple.

Im kinda lost on this part.Do you mean cut the bend off the elbow and sand the bottom of it till its round,the base part of the elbow that looks like a nut or a wrench gos on it?Make that round so the fuel line slides all the way down to the base of the regulator?Thank you sooo much for the help .

Hey Flyinghigh.

I run quite a few of the OS with the Cline mods. They are great running. I had the CSpec like I think you are getting and it ran well. I upgraded to the HZ this past summer, again with the cline mod.

For a check valve, I actually us one from a YS engine (the larger of the two models they make....I don't rememeber the part number off the top of my head but can look it up if you want).

I fly both at the DAM field when I am in the Metro area and also fly with the Mount Pleasant club.

The needle settings that Jim said are pretty close but I would go a bit richer all the way around just to be safe. That of course is presuming you are using CY Wildcat 30 percent (which is what I run). If not then the numbers will be different.

Do you mean cut the bend off the elbow and sand the bottom of it till its round,the base part of the elbow that looks like a nut

That part you are looking at is a plastic 90 degree bend the slips over a nipple on the regulator. It is not glued on and as such you should be able to lift it off (providing the other owner did not glue it on).

Because of the fact it is not glued on, people have had problems with it coming off in flight due to vibrations and of course the engine quits. What most do (myself included) is to not use that 90 degree bend, and in fact put the fuel line straight on the regulator. I use a small tie wrap to secure the line to the nipple.

it's better to ask for forgiveness than for permission

Rocket beat me to it...

That 90 degree elbow is a separate part that is a press-fit onto the round nipple that is on the body of the regulator itself. If you look through the posts here on RR, you'll see that many have tried to glue that elbow onto the regulator. Many have had poor results trying to glue it on.

You should ask the person from whom you are buying the motor if he glued that elbow on. If you can get it off the regulator without damaging the regulator itself, you will be much better off in the long run.

FWIW, I did use the duckbill when I first got the setup many years ago but I just liked the YS better. Maybe no difference just what I ended up liking

Thanks so much for the Replys everyone .
I see what you guys mean about the elbow.It slides "over" a nipple so the elbow doesn't screw in the Reg like I thought,just pull the elbow off,slide the fuel line on the nipple and zip tie it on.I have the needle setting wrote down and i'll go 3 clicks more on the high and mid setting to be on the safe side then tune from there.

jsenicka,

at 15000 to 15250 in idle up for the motor rpms,would you happen to maybe know what head speed that will be.This is going in a Raptor 90 is it helps.I just know some will say somthing like 1850 (just a example) and that could be a tad bit past the power band of the motor..

rocket_33,
I your about 4hrs away from me so if I end up having problems would it be ok if I dorve down to where your at?Once summer gets here that is haha..
Once again guys,thank you for all the help and advice .

rocket_33,
I your about 4hrs away from me so if I end up having problems would it be ok if I dorve down to where your at?Once summer gets here that is haha..
Once again guys,thank you for all the help and advice .

I would be glad to help, no problem, we can get together to fly. 4 hours seems a bit off. From Detroit to Mt Pleasant is about 2 1/2 hours. How far are you away from the Detroit Aero Modelers field as I fly there alot as well. Either way will be happy to help.

What are you going to use for an exhaust? You will find it to be a strong motor that will run like a fine watch.

-----Dave

* Making the World Better -- One Helicopter at a time! *

Team Heliproz

Im about 1hr away from the Detroit Aero Modelers field.I went there for the funfly they had (my very first one) when Big D's brother got married ..As for the pipe,im useing the one I have now intill I have the money for a good one.Im sure i'll go to the Detroit Aero Modelers field this summer a few times,thats a very nice site and I would love to fly there.

dkshema,
Not sure what gear ratio I have but i'll find out in a bit,thanks for letting me know theres more than one as I had no ideal haha..

I think there is even a 8 to 1 gearing option as well. If you have a choice I would suggest getting as close as you can to 8 to 1 (might be a pinion change) because that would put you with great head speed and put the engine right in its sweet spot.

You might want to keep an eye out for a better muffler though, I am not sure but I think I have heard issues about tuning with the one you have. Funtech is really good, so is Hatori and even the Muscle Pipe would be good